It is generally known to form various types of plastic blow-molded containers with hollow double-wall construction. These known types of blow-molded containers are formed by positioning extruded plastic tubular material of oblong cross section, usually referred to as a parison, between spaced-apart and complimentary mold parts. One mold part is provided with cavities that form the exterior of the container while the other mold part is provided with cavities that form the interior of the container. When the mold parts are brought together, the parison is inflated so that opposed wall portions are forced into the cavities of the mold parts to provide the double-wall construction of the container. The wall portions of the parison are pinched together by areas of the mold parts so that the exterior and interior walls of the container are joined together around their peripheral edges.
In some cases, a single piece blow-molded container is formed in one operation by simultaneously molding the body of the container and the cover or lid in side-by-side relationship and with an integral flexible "living" hinge joining the body and cover or lid. Examples of these known types of plastic blow-molded containers are illustrated in U.S. Pat. Nos. 3,327,841; 3,339,781; 3,441,071; 3,452,125; 3,536,435; and 4,340,139.
The body of the containers formed in the manner illustrated in these patents has the side walls molded in a right angular relationship with the bottom wall and the side walls are integrally connected at the corners of the container. This method of blow molding the container body limits the height of the side walls and thereby limits the depth of the body of the container. The height of the side walls is limited because of the limitation of the depth of the cavity which can be formed in one mold part and the limitation of the corresponding protrusion which can be formed in the other mold part.